298 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



C. THE RELATIVE VARIABILITY OF DWARF AND NORMAL EGGS. 



Table 2 gives also the data for comparing the variability of 

 the different classes of prolate spheroidal dwarf eggs with 

 each other and with normal eggs. In comparing classes where 

 the absolute difference in size is as great as it is between 

 normal and dwarf eggs the coefficients of variation are more 

 accurate measures of relative variability than are the standard 

 deviations. In order to determine whether or not the apparent 

 differences in degree of variability shown by the several classes 

 is significant it is necessary to compare the coefficient of varia- 

 tion (given in Table 2) for each character in each group with 

 the coefficient of variation for the same character in each of the 

 other groups. If such comparisons are made, and if in each case 

 the difference in the coefficients compared is considered in rela- 

 tion to its probable error, we find the following relations between 

 the degree of variability in the several classes.. First, normal 

 eggs are significantly less variable than the least variable class 

 of dwarf eggs (small yolked dwarfs) in length, breadth, egg 

 weight, yolk weight and probably shell weight. The significance 

 of the smaller variation in albumen weight is doubtful. Second, 

 small yolked dwarf eggs are almost certainly less variable than 

 other dwarf eggs in length and probably also in weight. The 

 significance of the smaller variation in breadth is doubtful. 

 Third, the somewhat greater variation in every size character 

 in the dwarf eggs with free yolk than in the yolkless eggs is 

 not certainly significant. That is, it may be due to errors in 

 sampling. In respect of shape the only deviation which can 

 be considered of even probable significance is the difference 

 between yolkless and small yolked dwarfs. That is, normal 

 eggs and small yolked dwarf eggs are probably less variable in 

 shape than dwarf eggs without a formed yolk. 



The relative variability of the size characters within each 

 group are also of some interest. In both normal and dwarf 

 eggs the size characters may be arranged in the order of their 

 variability as egg weight, length, and breadth. 



